amazon jp的Prime membership無法取消 - 海外購物

各位大大好，
我前幾天去日本玩，先行上amazon jp購物，
當時有點選Prime membership，
之後上銀行網站發現有收取3900年費，
所以寫信給amazon jp客服：
I started my amazon prime free trial few days ago, and recently found that
you charged me JPY3900 for this service. Then I realized that I forgot to
cancel my prime membership but the sevice is uneconomic for me as I rarely
buy things on amazon. I did not use this sevice any more after the trial
period and JPY3900 is not a small sum for me. Would you please be so kind to
help me cancel my prime membership and give the money back to me?

客服回信：
If you haven't used Amazon Prime membership benefits, we can cancel the
membership and make a refund for the membership fee.

However I found that you have used Amazon Prime membership benefits on your
orders. Therefore we are unable to cancel the membership. We are sorry for
this inconvenience and thank you for your understanding.

The promotion is active until January 21 in 2016.

我一年前有試用過，也取消過，
這次沒注意到就在按下去，
似乎變成正式期間會員，
其中購物兩天有使用數次，
不知要如何跟客服溝通退年費呢？
謝謝~~

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